| 1 | package config |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "crypto/sha256" |
| 6 | "fmt" |
| 7 | "os" |
| 8 | osuser "os/user" |
| 9 | "path/filepath" |
| 10 | "runtime" |
| 11 | "slices" |
| 12 | "sort" |
| 13 | "strings" |
| 14 | "sync" |
| 15 | "sync/atomic" |
| 16 | "time" |
| 17 | |
| 18 | filelock "reasonix/internal/identitylock" |
| 19 | ) |
| 20 | |
| 21 | // userEditMu serializes in-process read-modify-write cycles. The public lock |
| 22 | // helpers also take a path-derived advisory file lock, so CLI, Desktop, bot, and |
| 23 | // other Reasonix processes cannot save stale snapshots over one another. |
| 24 | // Desktop's read-only config loads (tray/view/bot-runtime paths) never write: |
| 25 | // they apply legacy migrations in memory only, and the migrated form reaches |
| 26 | // disk through the first locked write path (loadDesktopUserConfigForEdit, |
| 27 | // called with this lock held). |
| 28 | var ( |
| 29 | userEditMu sync.Mutex |
| 30 | configEditPinsMu sync.RWMutex |
| 31 | configEditPins = map[string]string{} |
| 32 | userEditFileLockFailure atomic.Pointer[configEditLockFailure] |
| 33 | userConfigEditLockTimeout = 5 * time.Second |
| 34 | configEditLockTimeout = 5 * time.Second |
| 35 | ) |
| 36 | |
| 37 | type configEditLockFailure struct { |
| 38 | err error |
| 39 | } |
| 40 | |
| 41 | type configEditTarget struct { |
| 42 | logicalKey string |
| 43 | resolvedPath string |
| 44 | lockPath string |
| 45 | } |
| 46 | |
| 47 | // LockUserConfigEdits acquires the process-wide user-config edit lock and |
| 48 | // returns the unlock. Hold it across the full LoadForEdit→mutate→SaveTo |
| 49 | // cycle; do not hold it across controller rebuilds or other slow non-config |
| 50 | // work, and never call another LockUserConfigEdits taker while holding it. |
| 51 | func LockUserConfigEdits() func() { |
| 52 | userEditMu.Lock() |
| 53 | target, err := resolveConfigEditTarget(UserConfigPath()) |
| 54 | var unlockFile func() |
| 55 | if err == nil { |
| 56 | unlockFile, err = acquireConfigEditLockPathWithTimeout(target.lockPath, userConfigEditLockTimeout) |
| 57 | } |
| 58 | clearPins := func() {} |
| 59 | if err != nil { |
| 60 | userEditFileLockFailure.Store(&configEditLockFailure{err: err}) |
| 61 | } else { |
| 62 | clearPins = activateConfigEditPins([]configEditTarget{target}) |
| 63 | } |
| 64 | var once sync.Once |
| 65 | return func() { |
| 66 | once.Do(func() { |
| 67 | clearPins() |
| 68 | if unlockFile != nil { |
| 69 | unlockFile() |
| 70 | } |
| 71 | userEditFileLockFailure.Store(nil) |
| 72 | userEditMu.Unlock() |
| 73 | }) |
| 74 | } |
| 75 | } |
| 76 | |
| 77 | // LockConfigFileEdits serializes a configuration read-modify-write transaction |
| 78 | // with both other goroutines and other Reasonix processes. The cross-process |
| 79 | // lock lives in an OS-user registry rather than beside path, so project |
| 80 | // repositories do not accumulate lock files. |
| 81 | func LockConfigFileEdits(path string) (func(), error) { |
| 82 | return lockConfigFilesEdits(path) |
| 83 | } |
| 84 | |
| 85 | // LockConfigFilesEdits locks multiple config sources as one transaction. |
| 86 | // Aliases that resolve to the same final file share one advisory lock, and |
| 87 | // every logical path stays pinned to the resolved target until unlock. |
| 88 | func LockConfigFilesEdits(paths ...string) (func(), error) { |
| 89 | return lockConfigFilesEdits(paths...) |
| 90 | } |
| 91 | |
| 92 | // EditConfigFile runs a strict read-modify-write transaction for one TOML |
| 93 | // config. Malformed input is returned to the caller and is never replaced with |
| 94 | // defaults. The callback must only mutate cfg; keep slow runtime work outside |
| 95 | // the transaction. |
| 96 | func EditConfigFile(path string, edit func(*Config) error) error { |
| 97 | return editConfigFile(path, true, edit) |
| 98 | } |
| 99 | |
| 100 | // EditConfigFileWithoutCredentials is EditConfigFile without loading the |
| 101 | // Reasonix credential environment. |
| 102 | func EditConfigFileWithoutCredentials(path string, edit func(*Config) error) error { |
| 103 | return editConfigFile(path, false, edit) |
| 104 | } |
| 105 | |
| 106 | func editConfigFile(path string, loadCredentials bool, edit func(*Config) error) error { |
| 107 | if edit == nil { |
| 108 | return fmt.Errorf("edit config: nil callback") |
| 109 | } |
| 110 | unlock, err := LockConfigFileEdits(path) |
| 111 | if err != nil { |
| 112 | return err |
| 113 | } |
| 114 | defer unlock() |
| 115 | cfg, err := loadForEditStrict(path, loadCredentials, false) |
| 116 | if err != nil { |
| 117 | return err |
| 118 | } |
| 119 | if err := edit(cfg); err != nil { |
| 120 | return err |
| 121 | } |
| 122 | return cfg.SaveTo(path) |
| 123 | } |
| 124 | |
| 125 | // lockConfigFilesEdits acquires one in-process transaction lock plus every |
| 126 | // distinct path-derived file lock in a stable order. Stable ordering prevents |
| 127 | // two Reasonix processes editing overlapping config-source sets from deadlocking. |
| 128 | func lockConfigFilesEdits(paths ...string) (func(), error) { |
| 129 | userEditMu.Lock() |
| 130 | targets := make([]configEditTarget, 0, len(paths)) |
| 131 | seenLogical := make(map[string]struct{}, len(paths)) |
| 132 | for _, path := range paths { |
| 133 | if strings.TrimSpace(path) == "" { |
| 134 | continue |
| 135 | } |
| 136 | target, err := resolveConfigEditTarget(path) |
| 137 | if err != nil { |
| 138 | userEditMu.Unlock() |
| 139 | return nil, err |
| 140 | } |
| 141 | if _, ok := seenLogical[target.logicalKey]; ok { |
| 142 | continue |
| 143 | } |
| 144 | seenLogical[target.logicalKey] = struct{}{} |
| 145 | targets = append(targets, target) |
| 146 | } |
| 147 | if len(targets) == 0 { |
| 148 | userEditMu.Unlock() |
| 149 | return nil, fmt.Errorf("lock config edits: no config paths") |
| 150 | } |
| 151 | |
| 152 | lockPaths := make([]string, 0, len(targets)) |
| 153 | seenLocks := make(map[string]struct{}, len(targets)) |
| 154 | for _, target := range targets { |
| 155 | if _, ok := seenLocks[target.lockPath]; ok { |
| 156 | continue |
| 157 | } |
| 158 | seenLocks[target.lockPath] = struct{}{} |
| 159 | lockPaths = append(lockPaths, target.lockPath) |
| 160 | } |
| 161 | sort.Strings(lockPaths) |
| 162 | |
| 163 | ctx, cancel := context.WithTimeout(context.Background(), configEditLockTimeout) |
| 164 | defer cancel() |
| 165 | unlockFiles := make([]func(), 0, len(lockPaths)) |
| 166 | for _, lockPath := range lockPaths { |
| 167 | if err := os.MkdirAll(filepath.Dir(lockPath), 0o700); err != nil { |
| 168 | for _, v := range slices.Backward(unlockFiles) { |
| 169 | v() |
| 170 | } |
| 171 | userEditMu.Unlock() |
| 172 | return nil, fmt.Errorf("lock config edits: create lock directory: %w", err) |
| 173 | } |
| 174 | unlockFile, err := acquireConfigEditLockPath(ctx, lockPath) |
| 175 | if err != nil { |
| 176 | for _, v := range slices.Backward(unlockFiles) { |
| 177 | v() |
| 178 | } |
| 179 | userEditMu.Unlock() |
| 180 | return nil, fmt.Errorf("lock config edits: %w", err) |
| 181 | } |
| 182 | unlockFiles = append(unlockFiles, unlockFile) |
| 183 | } |
| 184 | clearPins := activateConfigEditPins(targets) |
| 185 | |
| 186 | var once sync.Once |
| 187 | return func() { |
| 188 | once.Do(func() { |
| 189 | clearPins() |
| 190 | for _, v := range slices.Backward(unlockFiles) { |
| 191 | v() |
| 192 | } |
| 193 | userEditMu.Unlock() |
| 194 | }) |
| 195 | }, nil |
| 196 | } |
| 197 | |
| 198 | func acquireConfigFileEditLockWithTimeout(path string, timeout time.Duration) (func(), error) { |
| 199 | target, err := resolveConfigEditTarget(path) |
| 200 | if err != nil { |
| 201 | return nil, err |
| 202 | } |
| 203 | return acquireConfigEditLockPathWithTimeout(target.lockPath, timeout) |
| 204 | } |
| 205 | |
| 206 | func acquireConfigEditLockPathWithTimeout(lockPath string, timeout time.Duration) (func(), error) { |
| 207 | ctx, cancel := context.WithTimeout(context.Background(), timeout) |
| 208 | defer cancel() |
| 209 | return acquireConfigEditLockPath(ctx, lockPath) |
| 210 | } |
| 211 | |
| 212 | func acquireConfigEditLockPath(ctx context.Context, lockPath string) (func(), error) { |
| 213 | lockDir := filepath.Dir(lockPath) |
| 214 | if err := os.MkdirAll(lockDir, 0o700); err != nil { |
| 215 | return nil, fmt.Errorf("lock config edits: create lock directory: %w", err) |
| 216 | } |
| 217 | info, err := os.Lstat(lockDir) |
| 218 | if err != nil { |
| 219 | return nil, fmt.Errorf("lock config edits: inspect lock directory: %w", err) |
| 220 | } |
| 221 | if info.Mode()&os.ModeSymlink != 0 || !info.IsDir() { |
| 222 | return nil, fmt.Errorf("lock config edits: unsafe lock directory") |
| 223 | } |
| 224 | if err := os.Chmod(lockDir, 0o700); err != nil { |
| 225 | return nil, fmt.Errorf("lock config edits: secure lock directory: %w", err) |
| 226 | } |
| 227 | unlockFile, err := filelock.Acquire(ctx, lockPath) |
| 228 | if err != nil { |
| 229 | return nil, fmt.Errorf("lock config edits: %w", err) |
| 230 | } |
| 231 | return unlockFile, nil |
| 232 | } |
| 233 | |
| 234 | func configFileEditLockPath(path string) (string, error) { |
| 235 | target, err := resolveConfigEditTarget(path) |
| 236 | if err != nil { |
| 237 | return "", err |
| 238 | } |
| 239 | return target.lockPath, nil |
| 240 | } |
| 241 | |
| 242 | func resolveConfigEditTarget(path string) (configEditTarget, error) { |
| 243 | logicalKey, err := configEditPathKey(path) |
| 244 | if err != nil { |
| 245 | return configEditTarget{}, err |
| 246 | } |
| 247 | userOwned := isUserConfigPath(path) || samePath(path, legacyConfigPath()) || samePath(path, UserCredentialsPath()) |
| 248 | resolved, err := resolveConfigAccessPathUnpinned(path, userOwned) |
| 249 | if err != nil { |
| 250 | return configEditTarget{}, fmt.Errorf("lock config edits: %w", err) |
| 251 | } |
| 252 | lockPath, err := configFileEditLockPathResolved(resolved) |
| 253 | if err != nil { |
| 254 | return configEditTarget{}, err |
| 255 | } |
| 256 | return configEditTarget{ |
| 257 | logicalKey: logicalKey, |
| 258 | resolvedPath: resolved, |
| 259 | lockPath: lockPath, |
| 260 | }, nil |
| 261 | } |
| 262 | |
| 263 | func configFileEditLockPathResolved(resolved string) (string, error) { |
| 264 | lockDir, err := configEditLockRegistryDir() |
| 265 | if err != nil { |
| 266 | return "", err |
| 267 | } |
| 268 | lockKey := filepath.Clean(resolved) |
| 269 | if runtime.GOOS == "windows" || runtime.GOOS == "darwin" { |
| 270 | lockKey = strings.ToLower(filepath.ToSlash(lockKey)) |
| 271 | } |
| 272 | digest := sha256.Sum256([]byte(lockKey)) |
| 273 | return filepath.Join(lockDir, fmt.Sprintf("%x.lock", digest)), nil |
| 274 | } |
| 275 | |
| 276 | func configEditLockRegistryDir() (string, error) { |
| 277 | current, err := osuser.Current() |
| 278 | if err != nil { |
| 279 | return "", fmt.Errorf("lock config edits: resolve OS user: %w", err) |
| 280 | } |
| 281 | identity := strings.TrimSpace(current.Uid) |
| 282 | if identity == "" { |
| 283 | identity = strings.TrimSpace(current.Username) |
| 284 | } |
| 285 | if identity == "" { |
| 286 | identity = strings.TrimSpace(current.HomeDir) |
| 287 | } |
| 288 | if identity == "" { |
| 289 | return "", fmt.Errorf("lock config edits: OS user identity unavailable") |
| 290 | } |
| 291 | digest := sha256.Sum256([]byte(identity)) |
| 292 | if runtime.GOOS != "windows" { |
| 293 | // The OS-wide temporary root is invariant across process-specific TMPDIR |
| 294 | // overrides. The per-user directory is verified and forced to mode 0700 |
| 295 | // before the advisory lock file is opened. |
| 296 | return filepath.Join(string(filepath.Separator), "tmp", fmt.Sprintf("reasonix-config-locks-%x", digest[:8])), nil |
| 297 | } |
| 298 | home := strings.TrimSpace(current.HomeDir) |
| 299 | if home == "" { |
| 300 | return "", fmt.Errorf("lock config edits: OS user home unavailable") |
| 301 | } |
| 302 | return filepath.Join(filepath.Clean(home), ".reasonix", "locks", fmt.Sprintf("config-edits-%x", digest[:8])), nil |
| 303 | } |
| 304 | |
| 305 | func configEditPathKey(path string) (string, error) { |
| 306 | path = strings.TrimSpace(path) |
| 307 | if path == "" { |
| 308 | return "", fmt.Errorf("lock config edits: empty config path") |
| 309 | } |
| 310 | abs, err := filepath.Abs(filepath.Clean(path)) |
| 311 | if err != nil { |
| 312 | return "", fmt.Errorf("lock config edits: resolve path: %w", err) |
| 313 | } |
| 314 | if runtime.GOOS == "windows" { |
| 315 | abs = strings.ToLower(filepath.ToSlash(abs)) |
| 316 | } |
| 317 | return abs, nil |
| 318 | } |
| 319 | |
| 320 | func activateConfigEditPins(targets []configEditTarget) func() { |
| 321 | configEditPinsMu.Lock() |
| 322 | for _, target := range targets { |
| 323 | configEditPins[target.logicalKey] = target.resolvedPath |
| 324 | } |
| 325 | configEditPinsMu.Unlock() |
| 326 | var once sync.Once |
| 327 | return func() { |
| 328 | once.Do(func() { |
| 329 | configEditPinsMu.Lock() |
| 330 | for _, target := range targets { |
| 331 | delete(configEditPins, target.logicalKey) |
| 332 | } |
| 333 | configEditPinsMu.Unlock() |
| 334 | }) |
| 335 | } |
| 336 | } |
| 337 | |
| 338 | func pinnedConfigEditPath(path string) (string, bool) { |
| 339 | key, err := configEditPathKey(path) |
| 340 | if err != nil { |
| 341 | return "", false |
| 342 | } |
| 343 | configEditPinsMu.RLock() |
| 344 | resolved, ok := configEditPins[key] |
| 345 | configEditPinsMu.RUnlock() |
| 346 | return resolved, ok |
| 347 | } |
| 348 | |
| 349 | func currentUserConfigEditLockError() error { |
| 350 | if failure := userEditFileLockFailure.Load(); failure != nil { |
| 351 | return failure.err |
| 352 | } |
| 353 | return nil |
| 354 | } |
| 355 |